1. Field of the Invention
The present invention relates to a rotation angle limitation device and an electronic device comprising the rotation angle limitation device.
2. Description of the Related Art
There is prior technology whereby the screen of a notebook computer can be rotated along two rotational axes. The screen can be rotated in the opening direction, and it can also be rotated in a lateral direction. Usually, the notebook computer screen can be opened from 0 up to 180 degrees. Therefore, if the opening angle of the screen is too small (e.g., close to 0 degrees) or too large (close to 180 degrees), the screen casing could be easily scratched if one tries to rotate it laterally. Currently, there is no design to restrict lateral rotation movement of a notebook screen when the opening angle of the notebook is too small or too large.
In order to reduce scratching of the screen casing, the prior art has presented a method involving placing a wear-resistant rubber pad at the bottom of the screen. When the opening angle is large and the screen is rotated laterally, the rubber pad will be in direct contact with the hard surface such as the desktop, thus reducing damage to the screen casing. However, this method cannot prevent the screen casing from being scratched during a lateral rotation when the opening angle is very small.
In addition, the opening angle of a notebook computer lies between 0 degrees and 180 degrees. The general approach to maintain the screen in position is to introduce a positioning column that has a protruding-shape on the edge of the computer, and pairing the positioning column with concave shapes in order to secure the screen in a relative position to the laptop computer. However, the use of a positioning column will affect the appearance and also cause discomfort when touched by the users.
Therefore, it is necessary to provide a rotation angle limitation device and a portable electronic device comprising the rotation angle limitation device to resolve the above-mentioned problems.